1973 film by Bernard L. Kowalski
Sssssss is a 1973 American body horror film directed by Bernard L. Kowalski and starring Strother Martin, Dirk Benedict, and Heather Menzies. Its plot follows a college student who becomes a laboratory assistant to a herpetologist who is covertly developing a serum that can transform human beings into snakes.
The make-up effects were created by John Chambers and Nick Marcellino. It received a nomination for the Best Science Fiction Film award of the Academy of Science Fiction, Fantasy and Horror Films in 1975.
Plot summary adapted from Wikipedia, licensed under CC BY-SA 4.0.